When comparing Greenify vs Password Safe, the Slant community recommends Password Safe for most people. In the question“What are the best Material Design apps?”Password Safe is ranked 29th while Greenify is ranked 58th. The most important reason people chose Password Safe is:

Password Safe has a portable versiona, PasswordSafe2Go.
There is also PasswordSafe for U3 (still supported, but no longer available).

Pros

Pro

Even works without ROOT

Greenify even offers battery savings to non ROOT devices, though it may be limited compared to what can be done with ROOT and Xposed.

Pro

Hibernates, instead of freezing apps

Greenify's mane function is to hibernate any installed apps. This allows users to to quell overly active apps that are draining their battery without having to delete them. This can be done with or without ROOT.

Pro

Portable

Password Safe has a portable versiona, PasswordSafe2Go.There is also PasswordSafe for U3 (still supported, but no longer available).

Pro

Completely offline

This does not save or synch with any server; no connection to any external server. There is no central server to hack, no network connection to sniff.

Pro

Great user interface on Mac and iOS

Since the passwordSafe is essentially an open standard multiple people can use to develop apps. The http://pwsafe.info/ apps for Mac and iOS are really excellent (paid) management options.

Pro

Anyone can verify the code since the software is open source

Anyone can review the code.

Cons

Con

Greenifying without ROOT has to be done manually each time

When using Greenify without ROOT access to hibernate apps, it has to be done manually each time. There is a widget and shortcut that users can set to their home screen to make this action a bit easier though.

Con

Backups needed

You have to be diligent with your backups. You have to be careful when synching copies across your devices.